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Objective This study evaluated the effect of different impression and fabrication techniques—conventional casting and 3D printing—on the precision of metal post‐and‐core restorations. Methods and Materials A maxillary central incisor was designed in ExoCAD, and STL files of the reference tooth and the “ideal” post were saved; the reference tooth was additively manufactured in metal. Four workflows were compared (n = 10/group): (1) conventional impression with a direct resin pattern and casting (CO); (2) semi‐digital impression with an intra‐canal Duralay pattern plus Silicone pick‐up, laboratory scan, and direct metal printing (DS); (3) semi‐digital Full Silicone (putty/wash) impression, laboratory scan, and direct metal printing (FS); and (4) fully digital intraoral scanning with Medit i700 and direct metal printing (FD). For each specimen, the fabricated post STL was compared to the “ideal post” STL in Geomagic Control X to assess precision. Normality was tested with Shapiro–Wilk, and between‐group comparisons used one‐way analysis of variance in SPSS (α = 0.05). Results In forty specimens (FD, DS, FS, CO; n = 10/group), three outcomes were analyzed: In‐Tol, Over‐Tol, and Under‐Tol. In‐Tol differed significantly among groups (p < 0.001); Tamhane's T2 indicated FD > DS, FS, CO (p = 0.006, < 0.001, < 0.001). Over‐Tol differed significantly (p < 0.001); FD < FS (p < 0.001), FD < CO (p = 0.021), and DS < FS (p < 0.001). Under‐Tol also differed significantly (p < 0.001); DS > FD (p = 0.027), DS > FS (p = 0.011), and CO > FS (p = 0.016). Conclusion Fully digital, directly printed Co–Cr posts exhibited superior precision compared with conventional and semi‐digital workflows. While conventional casting remains reliable, direct metal printing appears to be a practical and potentially easier alternative.

Objectives This retrospective, non‐interventional study aimed to evaluate the longevity and factors influencing the success of custom‐fabricated polyetheretherketone (PEEK) post‐and‐cores in endodontically treated teeth (ETT). Material and Methods During the observation period (2019–2022), 63 patients received 100 customized PEEK post‐and‐cores. Clinical outcomes were analyzed based on the following parameters: age, gender, tooth type, tooth position, proximal contacts, remaining cavity walls, antagonist contacts, and final restoration. Kaplan–Meier analysis was used for the survival probability. Log‐rank tests were used to identify univariate associations between failure rates and other potential factors. Cox regression was used to assess the risk of failure and determine possible risks between the identified factors at a cut‐off point p‐value (0.25 in univariate analysis). Results The median follow‐up duration was 20.62 months, with a maximum of 40.57 months. 93 restorations were judged as successful and 99 teeth survived. The main failure type was decementation of the restoration (n = 4). The annual failure rate was 3.4%. Gender, remaining tooth structure, and final restoration were found to be correlated with success rates in the preliminary univariate analysis (Log‐rank tests) to determine the association between failure rates and potential factors. Multifactorial survival analysis (Cox regression) showed that teeth with coronal walls had a significantly lower failure risk than deprived teeth, even with the ferrule effect. (HR = 0.04; 95% CI for HR = 0.01–0.29; p = 0.002). Conclusions PEEK post‐and‐cores adapt well to clinical restorative needs and offer favorable short‐term clinical outcomes. The remaining cavity wall was a significant success rate predictor.

Background Post-and-core systems are frequently used when restoring endodontically treated teeth. CAD/CAM technologies contribute to post fabrication by improving material uniformity and adaptation to canal morphology. Additionally, 3D printing presents an emerging approach that constructs posts incrementally and may address certain limitations associated with traditional fabrication methods. The purpose of this in vitro study was to evaluate the fracture resistance of custom-made CAD/CAM posts and cores fabricated using milling and additive techniques compared to customized fiber posts. Materials and methods Twenty-one maxillary central incisors were randomly divided into three groups ( n  = 7): Group MP (milled posts), Group 3D (3D printed posts), and Group CF (customized fiber posts). The teeth were embedded in acrylic resin and prepared endodontically. Post spaces were created using standardized drills. For Groups MP and 3D, the post spaces were scanned, and posts were fabricated using CAD/CAM technology and 3D printing. In Group CF, posts were customized with resin composite. All posts were cemented with resin cement. The specimens were subjected to thermocycling for 5,000 cycles. Fracture resistance was measured using a universal testing machine, and failure modes were examined with a stereomicroscope. The Kruskal-Wallis test was used to compare the three groups. Failure mode data were reported as frequencies and percentages. Fisher’s Exact test was used to compare failure modes among the three groups. Results There was no statistically significant difference in fracture resistance among the three groups ( p  = 0.400) or in failure modes ( p  = 0.381). The 3D group exhibited the highest percentage of restorable failures (85.7%), while the Milled group showed the highest percentage of non-restorable failures (57.1%). Conclusions All post types demonstrated comparable fracture resistance and favorable failure modes when restoring anterior endodontically treated teeth. Milled composite blocks and 3D-printable materials effectively produced one-piece post-and-core structures using CAD/CAM technology with fracture resistance falling within the typical masticatory forces for maxillary anterior teeth.

Objective The demand for esthetics has increased in today's world and most parents prefer to preserve their children's primary anterior teeth until their natural exfoliation. However, an intracanal post is required to provide retention for reconstruction of severely damaged anterior teeth due to caries or trauma. Various materials and methods may be used for the fabrication of intracanal posts. This study assessed the fracture strength and fracture mode of primary canine teeth reconstructed with prefabricated and customized polyethylene and glass fiber posts. Materials and Methods This in vitro study evaluated 60 extracted primary canine teeth in four groups (n = 15). After pulpectomy and post space preparation with 4 mm depth, composite resin post, prefabricated glass fiber post (Whitepost), customized glass fiber post (Interlig), or customized polyethylene fiber post (Ribbond) were placed in the root canals to provide retention, and the tooth crown was restored with bulk‐fill composite resin. The fracture strength was then measured in a universal testing machine. The fracture mode was also evaluated visually. Results The mean fracture strength was 22.45 ± 5.06, 33.10 ± 8.5, 30.20 ± 7.33, and 32.61 ± 5.73 N/mm2 in the composite resin post, Whitepost, Interlig, and Ribbond groups, respectively. The fracture strength was significantly lower in the composite group than in the remaining three groups (p = 0.000). No other significant differences were found (p > 0.05). Also, no significant difference was observed among the study groups in the fracture mode (p = 0.241). Conclusion The composite resin post yielded a significantly lower fracture strength than the prefabricated and customized glass and polyethylene fiber posts, but the fracture mode was not significantly different among the four groups.